*[8] Communication with London was as yet by no means frequent, and far from expeditious, as the following advertisement of 1778 will show:--"For London: To sail positively on Saturday next, the 7th November, wind and weather permitting, the Aberdeen smack. Will lie a short time at London, and, if no convoy is appointed, will sail under care of a fleet of colliers the best convoy of any. For particulars apply," &c., &c. *[9] "The bottom under the foundations," says Mr. Gibb, in his description of the work, "is nothing better than loose sand and gravel, constantly thrown up by the sea on that stormy coast, so that it was necessary to consolidate the work under low water by dropping large stones from lighters, and filling the interstices with smaller ones, until it was brought within about a foot of the level of low water, when the ashlar work was commenced; but in place of laying the stones horizontally in their beds, each course was laid at an angle of 45 degrees, to within about 18 inches of the top, when a level coping was added. This mode of building enabled the work to be carried on expeditiously, and rendered it while in progress less liable to temporary damage, likewise affording three points of bearing; for while the ashlar walling was carrying up on both sides, the middle or body of the pier was carried up at the same time by a careful backing throughout of large rubble-stone, to within 18 inches of the top, when the whole was covered with granite coping and paving 18 inches deep, with a cut granite parapet wall on the north side of the whole length of the pier, thus protected for the convenience of those who might have occasion to frequent it."--Mr. Gibb's 'Narrative of Aberdeen Harbour Works.' CHAPTER X. CALEDONIAN AND OTHER CANALS. The formation of a navigable highway through the chain of locks lying in the Great Glen of the Highlands, and extending diagonally across Scotland from the Atlantic to the North Sea, had long been regarded as a work of national importance. As early as 1773, James Watt, then following the business of a land-surveyor at Glasgow, made a survey of the country at the instance of the Commissioners of Forfeited Estates. He pronounced the canal practicable, and pointed out how it could best be constructed. There was certainly no want of water, for Watt was repeatedly drenched with rain while he was making his survey, and he had difficulty in preserving even his journal book. "On my way home," he says, "I passed through the wildest country I ever saw, and over the worst conducted roads."